docs: def pages_dynamic_tree_menu(context, page, url='/'):
      """
      Render a "dynamic" tree menu, with all nodes expanded which are either
      ancestors or the current page itself.
  
      Override ``pages/dynamic_tree_menu.html`` if you want to change the
      design.
  
      :param page: the current page
      :param url: not used anymore
      """
      lang = context.get('lang', pages_settings.PAGE_DEFAULT_LANGUAGE)
      page = get_page_from_string_or_id(page, lang)
      children = None
      if page and 'current_page' in context:
          current_page = context['current_page']
          # if this node is expanded, we also have to render its children
          # a node is expanded if it is the current node or one of its ancestors
          if(
              page.tree_id == current_page.tree_id and
              page.lft <= current_page.lft and
              page.rght >= current_page.rght
          ):
              children = page.get_children_for_frontend()
      context.update({'children': children, 'page': page})
      return context